chore: deleting common git service (#41992)

## Description
CE PR for the EE pr appsmithorg/appsmith-ee#9294

- This Pr is about removal of removal of commonGitService interface and
its implementation
- It also deletes some of existing test cases which has been
successfully migrated/duplicated with the new service.
- it contains some test cases which needs to be migrated to the newer
git service, hence those are disabled for now.

Fixes
#https://linear.app/appsmith/issue/V2-5516/removal-of-service-layer


## Automation

/ok-to-test tags="@tag.Git"

### 🔍 Cypress test results


## Communication
Should the DevRel and Marketing teams inform users about this change?
- [ ] Yes
- [ ] No

<!-- This is an auto-generated comment: Cypress test results  -->
> [!TIP]
> 🟢 🟢 🟢 All cypress tests have passed! 🎉 🎉 🎉
> Workflow run:
<https://github.com/appsmithorg/appsmith/actions/runs/29307122107>
> Commit: f9755e5
> <a
href="https://internal.appsmith.com/app/cypress-dashboard/rundetails-65890b3c81d7400d08fa9ee5?branch=master&workflowId=29307122107&attempt=1"
target="_blank">Cypress dashboard</a>.
> Tags: `@tag.Git`
> Spec:
> <hr>Tue, 14 Jul 2026 05:12:24 UTC
<!-- end of auto-generated comment: Cypress test results  -->


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Refactor**
  * Centralized Git profile handling via the Git profile utility.
* Removed deprecated Git service interfaces/implementations and related
compatibility layers.
* **Tests**
  * Removed the Git branches end-to-end integration test suite.
* Added a larger Git service end-to-end test class, currently disabled.
  * Updated user data tests to use the consolidated Git profile utility.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: sondermanish